This invention generally relates to a mold for forming plastic caps and to a method of removing plastic caps therefrom, and more specifically to such molds and methods involving plastic caps of the type having a tamper indicating ring frangibly connected to a skirt portion of the cap.
Tamper evident container caps are widely used to demonstrate to the final consumer that the contents of a container have not been contaminated or adulterated subsequent to the time the cap was initially secured to the container. One type of tamper evident cap employs a separable ring connected to a bottom edge of a skirt portion of the cap by a plurality of axially extending discrete, small frangible members that are circumferentially spaced around the cap. The ring includes an inside annular rib which, in use on the container, is located below a cooperating outwardly extending rib on the neck of the container. As the cap is twisted off the container, contact between the outside rib on the container neck and the inside rib on the separable ring of the cap breaks the previously mentioned frangible members, separating the ring from the remainder of the cap.
Providing a molded container cap with a tamper indicating ring as described above complicates the manufacture of that cap in several respects. The formation of the ring and the frangible members connecting the ring to the skirt of the cap requires that the mold used to form the cap have corresponding recesses and protrusions which complicates removal of the cap from the mold. Also, the cap must be removed from the mold in a way that does not break the frangible members of the cap since, of course, otherwise the cap cannot be used in the intended manner.